The first time one of us visited Seattle they were building the downtown bus tunnel. It was our introduction to "Welcome To Seattle - Sidewalk Closed". While New York City has its share of frenetic construction, the sidewalks are kept open. You might have to snake your way through an array of girders and pillars and hanging utility lights, but the street is open. Seattle, in contrast, allows developers to simply close the sidewalks. Seattle is not the most pedestrian friendly town.
The bus tunnel was closed again more recently, but it has now reopened. Interestingly, we never actually saw the original tunnel, so we will have to assume that things have changed. In any case, the newly remodeled tunnel is quite pretty and well appointed. Now, we have to wait for the airport light rail connection in 2009. It's nice to see some serious public works in this day and age.